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Robots, children's blocks, wooden clocks, its all good! Here's my idea and here's the [[page]] on RepRap's wiki where we can log in and click "edit".
Re: Assargadon's self-introduction. - 16 years ago
The server hosting the picture: seems to be down. I assume you are describing a x-y-z 3-axis machine, rather than something like an human arm or tripod. How big is it? Would it also be useful as a CNC router? My first step would be to contact the manufacturer of the machine to get the documentation and software. Hopefully you will be able to use the existing motors. You should be able to fiby SebastienBailard - Russia RepRap User Group
Re: Russia - 16 years ago
>I don't think it's right time now to announce Russian group on builders.reprap.org >before someone from russia build something reprap-related. If you're looking for other people as collaborators, it may be useful. I'll mention all the user groups in one big posting some time this week. >By the way, do I miss the e-mail annoucment about creating the russian group I >request, orby SebastienBailard - Russia RepRap User Group
Re: Alternate parts - 16 years ago
mcmaster is known for being expensive. They have everything, though, and ship For threaded rod and smooth rod, try your local steel supplier in the yellow pages. It should be cheaper than best buy. (They stock the stuff in big lengths, I ended up getting my rod cut down to 10 foot sections, and then I cut the smaller lengths at home.)by SebastienBailard - Mechanics
Re: Alternate parts - 16 years ago
Dylan: >My main concern though is the MXL belt. They also have the .080 pitch 1/4" but I >can't understand the pricing table, any ideas? These are closed loops of belt, aka "endless loop belt". The first entry, TB4-036MXL, has 36 teeth, and is 2.88 inch in perimeter. The last entry is only 18.00 inch in perimeter. This is no good. I think you need ~16 feet of belt, so you'll have toby SebastienBailard - Mechanics
Re: Marketplace for selling things (assembled electronic boards, etc) - 16 years ago
I want a marketplace forum as well. I'll run it by the core cabal and see if they're ok with it. It may be a few days to get a response.by SebastienBailard - Administration, Announcements, Policy
Re: Users groups - too many forums - consolidate Texas - 16 years ago
I'll create a Texas-wide forum if you like. I'm not going to nuke the Austin forum just yet, I need to re-ping a bunch of Austin folk who signed my clipboard at the maker faire.by SebastienBailard - Administration, Announcements, Policy
Re: active users listed at bottom of forum list page - 16 years ago
That's user-controlled behavior, if they've ticked off "Allow other users to see when I am logged in" under "Edit My Privacy Options". It appears to be enabled by default. Our forum software may be flaky about it though. One thing I want to implement is having user location posted under the user name for posts. I'll look into it after the server move.by SebastienBailard - Administration, Announcements, Policy
Object Reconstruction from Photographs - 16 years ago
Object reconstruction is using a computer to build up a 3D model from a dataset. In this case, the researchers used a bunch of photographs of buildings (like Notre Dame Cathedral) from flickr: They start out with random photos with no explicit camera position data and end up with a (slightly lumpy) digitalized model of the building. This is applicable to RepRap because we'd be able to use a diby SebastienBailard - 3D Scanners, Book Scanners, and Optics
Re: Printing solar panels and batteries - 16 years ago
I wonder how hard it would be to beat NanoSolar's efficiencies of scale. They're using big printing presses to make huge sheets of this stuff.by SebastienBailard - Let's design something! (I've got an idea ...)
Re: Plans or Specs for a Super-Sturdy RepStrap - 16 years ago
Have you looked at the jgro plans and Patrick Hood-Daniel's design for his machine? What is your budget, and how big a machine do you want to make? And have you considered just cnc-converting one of these or these: More background:by SebastienBailard - CNC Routers, Mills, and Hybrid RepRapping
Re: What about the use of UV glues and UV light - 16 years ago
Gack? Window glass? Very hard to machine, and the instant you overtighten a fastener, *pang!*.by SebastienBailard - Polymer Working Group
Re: Beads Instead of Teeth? - 16 years ago
Sean, Poke around on cnczone; I think people tend to avoid roller chain in larger cnc machines in favor of belt drives or gear rack. Not to say that you can't get it to work: I brought up chain drives with Ed some time ago. He'd considered using them with darwin but they wouldn't fit.by SebastienBailard - General
Re: Better self-replicating through 'flexonics' - 16 years ago
Email Jeremy Risner too. As a grad student, he may have the free time to compose more than a polite 3 line response. It would be extremely useful to bring in some folk with experience, and they just built such a machine.by SebastienBailard - General
Re: Dedicated Mailing Lists - 16 years ago
We're about to move servers (in 1-3 weeks I think) so it may take a little while.by SebastienBailard - Administration, Announcements, Policy
Better self-replicating through 'flexonics' - 16 years ago
This is the current paper I'm reading: www.cs.berkeley.edu/~risnerj/flexonics/wafr2002.pdf A bit more at: www.cs.berkeley.edu/~risnerj/flexonics/ Instead of using traditional motors, joints and sliding parts, and such, the idea is to print everything at once, using electroactive polymers and strategic flexixion (bending). The researchers have ended up building an inkjet-based 3D printer becauseby SebastienBailard - General
Bronze Clay - 16 years ago
Here is a very fascinating thread by some sculptors about bronze clay. Bronze clay, or bronze wax is a mass of bronze powder particles held together with some kind of binder. The material is either hand shaped or shaped in a mold and then sintered in a oxygen-free or vacuum furnace. (Sintered = fused, like a clay pot from a kiln.) Details: I think this has applications to RepRap; there areby SebastienBailard - Casting and Moldmaking Working Group
Re: Introduction... - 16 years ago
>I can only use gravity casting to pour the priorly created gel (olygomer) phase > of polycaprolactones, because the melting point of the polycaprolactones would >be too high for the silicone mould to resist. That is odd. What temperature were you using for the polycaprolactone, and what kind of silicone mold material are you using? It sounds like you're using a heat-vulcanized silicoby SebastienBailard - Reprappers
Re: Anyone In the Salt Lake City area? - 16 years ago
(I'll be moving this thread to the Utah, Salt Lake City RepRap User Group on Monday Evening.) It will be over here:by SebastienBailard - Utah, Salt Lake City RepRap User Group
Requested a forum? Wondering what to do next? Post in it! - 16 years ago
Don't forget to post in the forum after it's been created for you! (It's human nature; people are more likely to hop into a forum to respond 'Yeah, I'm here' than to enter a forum and be the first one to post to it.)by SebastienBailard - Request a Local RepRap User Group
Re: Just for Python people... - 16 years ago
This looks fun: It's a python-based open source mathematics program, like maple or mathematica.by SebastienBailard - RepRap Host
Re: What about the use of UV glues and UV light - 16 years ago
Interesting design. A few questions: How big is the machine? Have you considered going with aluminum instead of plexiglass? Aluminum is much more stiff. You may be able to do light routing with your machine that way. When you're moving back and forth in the y-axis, the x-axis subassembly rides on top of the two y-axis drive screws. Imagine a bunch of back-and-forth y-axis motion: the wholeby SebastienBailard - Polymer Working Group
Re: Inkjet-based 3D printing resources - 16 years ago
I wonder; could one make a slurry of powdered bronze and monomer, squirt catalyst on the surface to make a hardened slice of the object, put down another thin layer of slurry, another squirt, and so on? Remove the object, pack it in aluminum oxide, refractory investment, or ceramic shell, and then fire it in a vacuum or reducing furnace, and voila: a nice bronze object. (I'll develop this partby SebastienBailard - Powder Printing and Selective Laser Sintering
Microfab inkjet print heads (special purpose for wax, polymers, and other random media) - 16 years ago
Here is a price quote from Microfab for their piezo type and thermo type inkjet heads. The price is for the head itself; Microfab will sell you just the head, a full inkjet 3D printer, or anything in between. NOTE: The prices are high compared to a repurposed inkjet-on-paper cartridge, but these are manufactured as special-purpose devices using presumably very expensive equipment and processes.by SebastienBailard - Plastic Extruder Working Group
Re: Inkjet-based 3D printing resources - 16 years ago
I found this, via google "viscosity inkjet" 'Rheological Characterisation of Inkjet Fluids' It looks like ~ 30 mPa s, but I'm not sure if that is the same stuff as real inkjet ink. Looking at microfab's inkjet-type print heads: "Fluids with viscosity less than 20 cp and surface tension in the range 20-70 dynes/cm can be dispensed." -This goes for both their high-temperature and low-temperatureby SebastienBailard - Powder Printing and Selective Laser Sintering
Re: Inkjet-based 3D printing resources - 16 years ago
There are two kinds, piezoelectric and thermo. *Piezoelectric uses a piezoelectric element to mechanically push the droplets out. *Thermo heats up a resistor. The heat creates a steam bubble in the (usually aqueous with thermo) ink, and that bubble pushes the droplet out. See:by SebastienBailard - Powder Printing and Selective Laser Sintering
Re: Furfuryl Alcohol resins (and Waterglass stuff too it seems 
) - 16 years ago
Viktor, I've created an inkjet forum here, and threw in a couple links to start a thread of inkjet-fabrication resources.by SebastienBailard - Polymer Working Group
Inkjet-based 3D printing resources - 16 years ago
*Fabrication using Ink Jet Printing : overview *'Inkjet Applications' by Matt Gilliland **The associated kits *The Piezoelectric Oligonucleotide Synthesizer And Microarrayer GPL driver board and software to control an inkjet-head robot that prints "customizeable DNA microarrays": Seems to have full documentation, lots of information. via *fab@home: Evan Malone is working on thisby SebastienBailard - Powder Printing and Selective Laser Sintering
Re: Furfuryl Alcohol resins (and Waterglass stuff too it seems ) - 16 years ago
Viktor, did you use limestone plaster or plaster of paris (gypsum plaster)? I'm assuming the latter. I seem to recall my sculpture teacher told me the latter is acidic, which is why it rusts your tools if you don't clean it off. I am not sure if this is true: I should get some pH test strips and verify for my own sake. I know when you're mixing up plaster, if you don't clean the old plasterby SebastienBailard - Polymer Working Group
Re: Plasma Cutting - 16 years ago
I know nothing about this subject. Reading the wikipedia entry on plasma torches, it says that they start up their plasma using a high voltage spark. (The implication being that it drops down to a lower voltage afterwards, when it only needs to maintain the plasma?) If your TIG can't start that plasma though, I imagine it's not going to work, sort of like a fluorescent light that can't startby SebastienBailard - RepLab Working Group
Re: Salt Lake City, Utah - 16 years ago
Forum created. Please hop in and introduce yourself. You are very welcome to announce the forum on the builders blog, builders.reprap.org, or if you like, I'll mention it on the main blog, blog.reprap.orgby SebastienBailard - Utah, Salt Lake City RepRap User Group